Mandibular Rami Implant: A New Approach in Mandibular Reconstruction.

PURPOSE: The mandible is an essential esthetic and functional component of the lower third of the face and its reconstruction has always been a challenge, especially after severe post-traumatic injuries. The purpose of the present report was to introduce a new approach of mandibular reconstruction in a patient who had lost the entire mandible except for the rami after being severely injured in a blast. MATERIALS AND METHODS: A new approach using a titanium mandibular rami implant technique was applied using computer-aided 3-dimensional virtual planning and rapid prototyping technology. A prosthetic component was supported by the mandibular implant, which achieved occlusion and dedicated function for the patient. RESULTS: This method offered precise adaptation of the implant and prosthesis and an easier surgical procedure, providing a shortened operation time, no donor site morbidity, and more predictable outcomes. CONCLUSION: This new technique allows reconstruction of large-scale mandibular defects that is not possible by conventional surgical methods.

Antibacterial Effect of Bacteriocin Isolated From Lactobacillus Plantarum ATCC 8014 on Postoperative Infection of Mandibular Fracture In Vivo.

OBJECTIVE: The primary objective of this study was to verify the effects of bacteriocin in treatment of postoperative infection of mandibular fracture in vivo. METHODS: Eighty-two mice were inoculated intravenously with staphylococcal suspensions. Bacterial cultures were obtained from implants. Blood samples were collected at 1, 2, 4, 6, and 8 hours after the injection of bacteriocins. RESULTS: Bacteriocins have significant inhibitory effects on Staphylococcus aureus (P < 0.05) and there are significant differences interleukin (IL)-8 and IL-10 in serum (P < 0.05). CONCLUSIONS: Bacteriocin isolated from L plantarum may be one of promising ways to control postoperative infection of mandibular fracture in vivo.

Simple prosthesis for a cancer patient with a segmental mandibulectomy and free fibula flap reconstruction: a clinical report.

Tumors of the mandible often necessitate the resection of a major portion of the body of the mandible as well as tissue from the tongue. Resection of the body of the mandible often leads to discontinuity of the mandible, affecting function to a large extent. While the rehabilitation of such defects with free fibula flaps may provide a certain level of stability to the mandible and aid in the prosthetic rehabilitation of these patients, the bulk of these flaps may create difficulties during prosthetic rehabilitation. The economic constraints of patients and/or their fear of implant surgery may also rule out prosthetic rehabilitation with implant-retained prostheses. This case report describes a simple and cost-effective method of prosthetic rehabilitation for a cancer patient who had undergone a segmental mandibulectomy followed by reconstruction with a free fibula flap.

[Reconstruction of mandibular bone defects using three-dimensional skull model and individualized titanium prosthetics from computer assisted design].

OBJECTIVE: To evaluate the feasibility and effectiveness of reconstruction of mandibular bone defects using three-dimensional skull model and individualized titanium prosthetics from computer assisted design. METHODS: Between July 2002 and November 2009, 9 patients with mandibular defects accepted restorative operation using individualized bone prosthetics. Among 9 cases, 4 were male and 5 were female, aged 19-55 years. The causes of mandibulectomy were benign lesions in 8 patients and carcinoma of gingival in 1 patient. Mandibular defects exceeded midline in 2 cases, involved condylar in 4 cases, and was limited in one side without involvement of temporo-mandibular joint in 3 cases. The range of bone defects was 9.0 cm x 2.5 cm-17.0 cm x 2.5 cm. The preoperative spiral CT scan was performed and three-dimensional skull model was obtained. Titanium prosthetics of mandibular defects were designed and fabricated through multi-step procedure of reverse engineering and rapid prototyping. Titanium prosthetics were used for one-stage repair of mandibular bone defects, then two-stage implant denture was performed after 6 months. RESULTS: The individualized titanium prosthetics were inserted smoothly with one-stage operative time of 10-23 minutes. All the cases achieved incision healing by first intention and the oblique mandibular movement was corrected. They all got satisfactory face, had satisfactory contour and good occlusion. In two-stage operation, no loosening of the implants was observed and the abutments were in good position with corresponding teeth which were designed ideally before operation. All cases got satisfactory results after 1-9 years of follow-up. At last follow-up, X-ray examinations showed no loosening of implants with symmetry contour. CONCLUSION: Computer assisted design and three-dimensional skull model techniques could accomplish the design and manufacture of individualized prosthetic for the repair of mandibular bone defects.

Biomechanical configurations of mandibular transport distraction osteogenesis devices.

Mandibular bone transport (MBT) distraction osteogenesis devices are used for achieving reconstruction of mandibular defects in a predictable way, with few complications, less complexity than other alternative surgical procedures, and minimal tissue morbidity. However, selection of appropriate MBT device characteristics is critical for ensuring both their mechanical soundness and their optimal distraction function for each patient's condition. This article assesses six characteristics of currently available MBT devices to characterize their design and function and to classify them in a way that assists the selection of the best device option for each clinical case. In addition, the present work provides a framework for both the biomechanical conception of new devices and the modification of existing ones.

Mandibular reconstruction and second generation locking reconstruction plates: outcome of 110 patients.

Mandibular reconstruction plates have revolutionized the treatment of mandibular continuity defects following ablative or trauma surgery. This retrospective study of patients requiring mandibular reconstruction over a six year period describes the authors' experience with second generation mandibular locking reconstruction plates and identifies complications and risk factors. The use of second-generation locking reconstruction plates for the treatment of mandibular continuity defects has a 36% complication rate, which includes plate fracture, screw loosening, plate exposure, wound infection and malocclusion. The average time frame until a hardware failure (plate fracture, screw loosening) occurs is 14 months. Plate exposure is closely associated with patients who received radiation therapy, and have lateral defects reconstructed with a plate only or plate/soft tissue flap reconstruction. Plate fracture was associated with lateral defects, the presence of a postoperative dentition, and a plate only or plate/soft tissue flap reconstruction. The authors recommend the use of a primary vascularized bone reconstruction. This provides additional soft tissue support around the plate to minimize the chances of exposure. It also provides osseous support for the plate, reducing the time frame the plate endures load bearing, and minimizing the risk of plate fracture.

[Experience in making up for the defects of mandible with titanium reconstructive plates].

A brief review of the adoption and the use of reconstructive titanium plates (RTP) to make up for the defects of the mandible is presented in the article. 33 patients aged from 19 to 63 were observed. The defects of various areas of the mandible from 3 to 15 cm were made up with RTP. In 10 patients there were combinations with other materials. The periods of observation were up to 8 years. Absence of complications during the whole period of observations is stated. Secondary osteogenesis induction has been noted as a result of RTP interaction with the bone and the periosteum. Attention is paid to the necessity to observe technical requirements of RTP application. It allows to use the plates in making up for the defects of mandible (including vast defects) in the course of long (not less than 8 years) periods. Respectivity of the study of conditions and factors influencing optimum reparative regeneration of bone tissue surrounding RTP is conformed.

[New condylar head system for temporary condylar reconstruction in ablative tumour surgery]. / Neu entwickeltes Kiefergelenkkopfimplantat zur temporären Kondylus-Rekonstruktion in der ablativen Tumorchirurgie.

BACKGROUND: Based on own retrospective studies a condylar head add-on system for immediate, temporary reconstruction in patients undergoing ablative surgery requiring the removal of the manibular condyle has been developed in cooperation with the Department of Oral and Maxillofacial Surgery of the University of Tennessee, USA, and the Association for the Study of Internal Fixation (AO/ASIF). PURPOSE: The design of the new condylar head add-on system and its use in an anatomical dissection study on a human cadaver are introduced and discussed. DESIGN AND FIRST EXPERIENCES: The condylar replacement is made of commercial pure titanium and is conceived as an add-on system. It consists of a reconstruction plate (2.4 Uni-LOCK-System) und an adaptable condylar head that can be fitted on either side. The offset of the condylar head in a medial direction allows anatomically correct positioning of the implant. The slanted oval head shall provide a large contact area while maintaining function of the mandibular joint. The height-adjustable positioning of the condylar head add-on with four different fixations plates facilitates an intraoperative vertical correction of the condylar head without necessary bending of a new reconstruction plate. A condylar head add-on used on both sides and combined with the frequently used 2.4 Uni-LOCK-plate benefits from reduced storekeeping and turns out to be advantageous from an economic point of view. PERSPECTIVE: An international, prospective multi-center study evaluating the intraoperative applicability of the new condylar head add-on system and its functional as well as aesthetic results during the first two postoperative years has started in September 2006.

Long-term outcome and factors influencing bridging plates for mandibular reconstruction.

Vascularized bone grafts have become the preferred method of mandibular reconstruction. However, the technique is considered to increase both the operating time and blood loss, which might be associated with an increased morbidity and mortality. We conducted a retrospective analysis of 100 consecutive patients who underwent immediate bridging plate reconstruction. The median follow-up duration was 70 months. The 5-year overall survival rate was 69.9%. Cox multivariate analysis revealed that red blood cell transfusion was an independent prognostic factor for the overall survival. The plate survival with no complications was 62.2% at 5 years. Anterolateral defects and preoperative radiotherapy emerged as an independent adverse factor for plate survival. The use of bridging plates is an option for lateral mandibular reconstruction with no preoperative irradiation to avoid the risk from blood transfusion.

Minimizing complications in the use of titanium condylar head reconstruction prostheses.

OBJECTIVE: The study goals were to evaluate the use of titanium condylar prostheses in the setting of tumor resection and to discuss the techniques used to minimize complications. STUDY DESIGN AND SETTING: We conducted a retrospective review of a case series in a tertiary care hospital. Six patients underwent mandibulectomy, including the condyle, with primary reconstruction using titanium condylar prostheses. Charts were reviewed for operative technique, pathology, and complications. RESULTS: Pathology included squamous cell carcinoma, Ewing's sarcoma, embryonic rhabdomyosarcoma, giant cell granuloma, and adenocarcinoma. Three patients are alive without disease. Follow-up spanned 6.4 years with premorbid occlusion established in all cases, and there were no prosthesis extrusions or erosions. The condylar head was wrapped in preserved joint capsule or adjacent temporalis muscle/fascia and secured with permanent purse-string sutures; careful duplication of the length, and angulation of the native mandible from the angle to the superior extent of the condylar head. CONCLUSION: Titanium condylar prostheses are a viable choice in the setting of tumor resection and reconstruction, with appropriate technical precautions.

Primary oromandibular reconstruction using free flaps and thorp plates in cancer patients: a 5-year experience.

BACKGROUND: Low-profile second-generation THORP titanium plates combined with soft tissues free flaps (forearm or TRAM) can be used for oromandibular reconstruction in patients with SCC in advanced stage (stage III-IV). METHODS: To evaluate long-term stability and possible complications of this reconstructive technique, we recorded, retrospectively, data of 25 patients with posterolateral oromandibular defects after tumor resection collected during a 5-year period. RESULTS: All free flaps were successfully transferred, although eight patients were initially seen with delayed hardware-related reconstructive complications: plate exposure in four patients and plate fracture in four patients. CONCLUSIONS: Nowadays, the state-of-the-art treatment for mandibular defects is primary bone reconstruction with bone free flaps, but in selected cases (elderly patients, poor performance status, posterolateral oromandibular defects, soft tissue defects much more important than bone defects) the association with THORP plate-soft tissue free flaps represents a good reconstructive choice.

Reconstruction of lateral mandibular defects with dynamic bridging plates.

The principle of mandibular reconstruction by dynamic bridging plates in association with a bone graft is based on the double bridge reconstruction method. However, the plate can be used alone. Our aim was to report the long-term results of this treatment for mandibular lateral defects in fragile patients. From 1993 to 1999, 38 consecutive patients had primary reconstructions with bridging plate for lateral mandibular defects. Their mean age was 58.4 years (26-86) and the mean follow-up was 50 months (6-89). Excluding removal of plates for local recurrences, the overall success rate was 78%. Plates were removed after a mean of 20.4 months (1-66). No plates fractured. Dynamic bridging plates allow an immediate and efficient reconstruction with reduced operating time and compare favourably with conventional plates. They can also be used as a stand-by for patients who are to have a delayed free flap reconstruction.